// days adjustment, defaulting calendar and adjustment
        private static Optional <DaysAdjustment> parseDaysAdjustment(CsvRow row, string leg, string daysField, string daysCalField, string cnvField, string calField)
        {
            int?daysOpt = findValue(row, leg, daysField).map(s => Convert.ToInt32(s));
            HolidayCalendarId     cal = findValue(row, leg, daysCalField).map(s => HolidayCalendarId.of(s)).orElse(HolidayCalendarIds.NO_HOLIDAYS);
            BusinessDayAdjustment bda = parseBusinessDayAdjustment(row, leg, cnvField, calField).orElse(BusinessDayAdjustment.NONE);

            if (!daysOpt.HasValue)
            {
                return(null);
            }
            return(DaysAdjustment.builder().days(daysOpt.Value).calendar(cal).adjustment(bda).build());
        }